Involuntary

WHAT IF MECHANICAL FAILURE CAUSES THE CAR TO STOP?

Involuntary stop

What do you do when your car suddenly stops? Reach for your cellphone, certainly. Meanwhile, it's always a good idea to try to find the fault. If the breakdown is accompanied by clanking noises, or if some of the wheels have locked up, then it's most likely a serious problem. If there was no noise then there's a good chance that something small has gone wrong.

The first step is to take a good look under the bonnet for broken wires, a broken fuel pipe or any other obviously broken or leaking component. If there's no obvious fault, then you can swing into action by performing the following checks:

1. What does the fuel gauge show? Running out of fuel happens to everybody occasionally.
2. Check for a high-tension spark. Remove one of the plug leads and hold it close to a metal part of the cylinder head while somebody else winds the starter, with the ignition switched on. Ensure that you are not touching any metallic part of the plug lead, or you may get a nasty shock, literally. You should see an intense blue spark, if it's weak and yellow, or if there is no sign of a spark, inspect the rotor arm underneath the distributor cap, ensuring that it is not broken, or worn out. Also check that the carbon brush in the center of the cap is making contact with the rotor arm. If these items are in good condition, look at the low tension side.
3. The low-tension wire runs from the ignition coil to the side of the distributor. It is a thin wire that often breaks off just where it enters the distributor. If it is intact, and if the car has an old-fashioned distributor with points, then you should take the distributor cap off and open the points slightly with a screwdriver while the ignition is switched on. A small spark should jump as you open the points. If the spark is visible then you can normally assume the low-tension side is fine, but if it is absent then there is some malfunction in the wiring. If the points are open when you remove the cap then you have to rotate the engine by means of the starter until they're in the closed position, before you try to open them.
4. The last check is to make sure that fuel is reaching the carburetor. Remove the top part of the air cleaner, and see if fuel squirts into the carb throat when you move the arm attached to the throttle butterfly.

These checks will normally locate a significant portion of the causes of roadside stoppages.

Tips provided by CARToday.com/CAR Magazine